3. Chemical Reactions

Stoichiometry

Stoichiometry - Limiting & Excess Reactant, Theoretical & Percent Yield - Chemistry

An unidentified metal M reacts with an unidentified halogen X to form a compound MX2. When heated, the compound decomposes by the reaction: 
When 1.12 g of MX2 is heated, 0.720 g of MX is obtained, along with 56.0 mL of X2 gas. Under the conditions used, 1.00 mol of the gas has a volume of 22.41 L.
(a) What is the atomic weight and identity of the halogen X?

A mixture of CuO and Cu2O with a mass of 10.50 g is reduced to give 8.66 g of pure Cu metal. What are the amounts in grams of CuO and Cu2O in the original mixture?

 Molar mass reactant, molar mass product. 

 The molar mass of the reactant is not needed. 

 Molar mass reactant, mole ratio of product to reactant from the balanced chemical equation, molar mass product. 

 Molar mass reactant, mole ratio of product to reactant from the balanced chemical equation. 

 Mole ratio of product to reactant from the balanced chemical equation. 

 Correct combination of conversion factors. 

 Set up the calculation using the dimensional analysis approach, using units to determine the problem set up. 

 In order to calculate the mass of a product in a chemical reaction from the number of moles of a reactant, which of the following describes all the conversion factors needed? 

An alternative method for producing hydriodic acid is the reaction of iodine with hydrogen sulfide:
H2S + I2 --> 2 HI + S
(a) How many grams of I2 are needed to react with 49.2 g of H2S?

Stoichiometry: Study Hall Chemistry #10: ASU + Crash Course

A method used by the U.S. Environmental Protection Agency 
(EPA) for determining the concentration of ozone in air is to pass 
the air sample through a “bubbler” containing sodium iodide, 
which removes the ozone according to the following equation: 
O31g2 + 2 NaI1aq2 + H2O1l2¡ 
O21g2 + I21s2 + 2 NaOH1aq2 
(b) How many grams of sodium iodide 
are needed to remove 1.3 mg of O3?

The reaction of tungsten hexachloride (WCl6) with bismuth gives hexatungsten dodecachloride (W6Cl12). WCl6 + Bi ---> W6Cl12 + BiCl3 Unbalanced
(b) How many grams of bismuth react with 150.0 g of WCl6?

The reaction of NH3 and O2 forms NO and water. The NO can be
used to convert P4 to P4O6, forming N2 in the process. The P4O6
can be treated with water to form H3PO3, which forms PH3 and
H3PO4 when heated. Find the mass of PH3 that forms from the
reaction of 1.00 g of NH3.

A liquid fuel mixture contains 30.35% hexane (C6H14), 15.85%
heptane (C7H16), and the rest octane (C8H18). What maximum
mass of carbon dioxide is produced by the complete combustion
of 10.0 kg of this fuel mixture?

Potassium superoxide, KO2, is often used in oxygen masks 
(such as those used by firefighters) because KO2 reacts with 
CO2 to release molecular oxygen. Experiments indicate that 2 
mol of KO21s2 react with each mole of CO21g2. 
(c) What mass of KO21s2 is needed to consume 18.0 g CO21g2? 
What mass of O21g2 is produced during this reaction?

The following diagram represents a high-temperature
reaction between CH4 and H2O. Based on this reaction, find
how many moles of each product can be obtained starting
with 4.0 mol CH4.

Based on this reaction, how many moles of H2 can be obtained starting with 4.0 mol CH4?

The YBa2Cu3O7 superconductor can be synthesized by the 
sol–gel method from a stoichiometric mixture of metal ethoxides 
followed by heating in oxygen. How many grams of 
Y1OCH2CH323 and how many grams of Ba1OCH2CH322 
are required to react with 75.4 g of Cu1OCH2CH322 and 
an excess of water? Assuming a 100% yield, how many 
grams of YBa2Cu3O7 are obtained?

The Mole: Avogadro's Number and Stoichiometry

The source of oxygen that drives the internal combustion
engine in an automobile is air. Air is a mixture of gases, principally
N2179%2 and O2120%2. In the cylinder of an automobile
engine, nitrogen can react with oxygen to produce
nitric oxide gas, NO. As NO is emitted from the tailpipe of
the car, it can react with more oxygen to produce nitrogen
dioxide gas. (c) The production of NOx gases is an unwanted
side reaction of the main engine combustion process
that turns octane, C8H18, into CO2 and water. If 85% of
the oxygen in an engine is used to combust octane and the
remainder used to produce nitrogen dioxide, calculate how
many grams of nitrogen dioxide would be produced during
the combustion of 500 g of octane.

Detonation of nitroglycerin proceeds as follows:
4 C3H5N3O91l2¡
12 CO21g2 + 6 N21g2 + O21g2 + 10 H2O1g2
(a) If a sample containing 2.00 mL of nitroglycerin 1density =
1.592 g>mL2 is detonated, how many moles of gas are produced?

The following diagram represents a high-temperature
reaction between CH4 and H2O. Based on this reaction, find
how many moles of each product can be obtained starting
with 4.0 mol CH4.
<img src="https://lightcat-files.s3.amazonaws.com/problem_images/bbf1a3e88c640e13-1664282077667.jpg" alt="" />
Based on this reaction, find how many moles of CO can be obtained starting with 4.0 mol CH4?

The oxidation of chromium solid is represented by the following equation:&nbsp;<img data-fr-image-pasted="true"src="https://static.studychannel.pearsonprd.tech/courses/general-chemistry/thumbnails/images/221e0469"class="fr-fic fr-dii">&nbsp;How many moles of chromium (III) oxide are produced when 34.69 g Cr reacts with excess oxygen gas?&nbsp;

Sulfuric acid dissolves aluminum metal according to the reaction:
2 Al(s) + 3 H2SO4(aq)¡Al2(SO4)3(aq) + 3 H2( g)
Suppose you want to dissolve an aluminum block with a mass of
15.2 g. What minimum mass of H2SO4 (in g) do you need? What mass of H2 gas (in g) does the complete reaction of the aluminum
block produce?

Stoichiometry Basic Introduction, Mole to Mole, Grams to Grams, Mole Ratio Practice Problems

During a period of discharge of a lead–acid battery, 402 g
of Pb from the anode is converted into PbSO41s2. (a) What mass of PbO21s2 is reduced at the cathode during this same
period?

Nickel(II) sulfate, used for nickel plating, is prepared by treat-ment of nickel(II) carbonate with sulfuric acid:
NiCO3 + H2SO4 --> NiSO4 + CO2 + H2O
(a) How many grams of H2SO4 are needed to react with 14.5 g of NiCO3?

A mixture of N21g2 and H21g2 reacts in a closed container
to form ammonia, NH31g2. The reaction ceases before
either reactant has been totally consumed. At this stage
3.0 mol N2, 3.0 mol H2, and 3.0 mol NH3 are present. How
many moles of N2 and H2 were present originally?

 This numerical value is the number of moles of ozone. 

 This numerical value is the number of moles of oxygen atoms. 

 Avogadro's number provides the conversion factor between molecules and moles and the molar mass between moles and mass. 

Calculate the mass of 4.50 &#215; 1025 O3 molecules.

One method to synthesize ionic solids is by the heating of
two reactants at high temperatures. Consider the reaction
of FeO with TiO2 to form FeTiO3. Determine the amount of
each of the two reactants to prepare 2.500 g FeTiO3, assuming
the reaction goes to completion.
(d) Determine moles and mass (g) of FeO required.

When the nickel–zinc battery, used in digital cameras, is recharged, the following cell reaction occurs: 
(a) How many grams of zinc are formed when 3.35 x 10^-2 g of Ni(OH)2 are consumed?

Acid spills are often neutralized with sodium carbonate or sodium hydrogen carbonate. For neutralization of acetic acid, the unbalanced equations are
112 CH3CO2H1l2 + Na2CO31s2 S
CH3CO2Na1aq2 + CO21g2 + H2O1l2 122 CH3CO2H1l2 + NaHCO31s2
CH3CO2Na1aq2 + CO21g2 + H2O1l2
(b) How many kilograms of each substance is needed to neu- tralize a 1.000-gallon spill of pure acetic acid 1density =
1.049 g>mL2?

Sodium azide (NaN3) yields N2 gas when heated to 300 °C, a reaction used in automobile air bags. If 1.00 mol of N2 has a volume of 47.0 L under the reaction conditions, how many liters of gas can be formed by heating 38.5 g of NaN3? The reaction is

In the preparation of iron from hematite, Fe2O3 reacts with carbon:
Fe2O3 + C --> Fe + CO2 Unbalanced
(a) Balance the equation. 
(b) How many moles of carbon are needed to react with 525 g of hematite?
(c) How many grams of carbon are needed to react with 525 g of hematite?

Magnesium metal burns in oxygen to form magnesium oxide, MgO. 
(b) How many grams of oxygen are needed to react with 25.0 g of Mg? How many grams of MgO will result?

Consider the balanced equation:
SiO2(s) + 3 C(s)¡SiC(s) + 2 CO(g)
Complete the table showing the appropriate number of moles of
reactants and products. If the number of moles of a reactant is
provided, fill in the required amount of the other reactant, as
well as the moles of each product that forms. If the number of
moles of a product is provided, fill in the required amount of each
reactant to make that amount of product, as well as the amount
of the other product that forms.
Mol siO2 Mol C Mol SiC Mol CO
_____ _____ _____ 10

Hard water contains Ca2+, Mg2+, and Fe2+, which interfere 
with the action of soap and leave an insoluble coating on 
the insides of containers and pipes when heated. Water softeners 
replace these ions with Na+. Keep in mind that charge 
balance must be maintained. (b) If the sodium is 
added to the water softener in the form of NaCl, how many 
grams of sodium chloride are needed?

The reaction between potassium superoxide, KO2, and CO2,
4 KO2 + 2 CO2¡2K2CO3 + 3 O2
is used as a source of O2 and absorber of CO2 in selfcontained
breathing equipment used by rescue workers.
(a) How many moles of O2 are produced when 0.400 mol of
KO2 reacts in this fashion?

Several brands of antacids use Al1OH23 to react with stomach
acid, which contains primarily HCl:
Al1OH231s2 + HCl1aq2¡AlCl31aq2 + H2O1l2
(b) Calculate the number of grams of HCl that can react
with 0.500 g of Al1OH23.

Pure oxygen was first made by heating mercury(II) oxide: 
HgO --> (heat) Hg + O2 Unbalanced
(a) Balance the equation. 
(b) How many grams of mercury and how many grams of oxygen are formed from 45.5 g of HgO?
(c) How many grams of HgO would you need to obtain 33.3 g of O2

Isooctane, C8H18, is the component of gasoline from which 
the term octane rating derives. 
(b) Assuming that gasoline is 100% isooctane, that isooctane 
burns to produce only CO2 and H2O, and that 
the density of isooctane is 0.792 g/mL, what mass of 
CO2 in kilograms is produced each year by the annual 
U.S. gasoline consumption of 4.6 * 1010 L?

The fat stored in a camel’s hump is a source of both energy and
water. Calculate the mass of H2O produced by the metabolism
of 1.0 kg of fat, assuming the fat consists entirely of tristearin
1C57H110O62, a typical animal fat, and assuming that during metabolism,
tristearin reacts with O2 to form only CO2 and H2O.

The industrial production of hydriodic acid takes place by treatment of iodine with hydrazine (N2H4):
2 I2 + N2H4 --> 4 HI + N2
(b) How many grams of HI are produced from the reaction of 115.7 g of N2H4 with excess iodine

Window glass is typically made by mixing soda ash (Na2CO3), limestone (CaCO3), and silica sand (SiO2) and then heating to 1500 °C to drive off CO2 from the (Na2CO3) and CaCO3. The resultant glass consists of about 12% Na2O by mass, 13% CaO by mass, and 75% SiO2 by mass. How much of each reactant would you start with to prepare 0.35 kg of glass?

A compound of formula XCl3 reacts with aqueous AgNO3 to yield solid AgCl according to the following equation: 
When a solution containing 0.634 g of XCl3 was allowed to react with an excess of aqueous AgNO3, 1.68 g of solid AgCl was formed. What is the identity of the atom X?

The complete combustion of octane, C8H18, a component of 
gasoline, proceeds as follows: 
2 C8H181l2 + 25 O21g2¡16 CO21g2 + 18 H2O1g2 
(b) How many grams of O2 are needed to burn 10.0 g of C8H18?

How many kilograms of CO2 does the complete combustion of
3.8 kg of n-octane produce?

The thermite reaction,
Fe2O3 + Al S Al2O3 + Fe
produces so much heat that the Fe product melts. This reaction
is used industrially to weld metal parts under water,
where a torch cannot be employed. It is also a favorite chemical
demonstration in the lecture hall (on a small scale).
(b) Calculate how many grams of aluminum are needed to
completely react with 500.0 g of Fe2O3 in this reaction.

The reaction of potassium chlorate and sucrose is given below:&nbsp;<img src="https://static.studychannel.pearsonprd.tech/courses/general-chemistry/thumbnails/images/67b90376"class="fr-fic fr-dii">If 2.33 x 10-7 formula units of potassium chlorate are reacted, how many grams of carbon dioxide will be produced?&nbsp;

An alternative method for producing hydriodic acid is the reaction of iodine with hydrogen sulfide:
H2S + I2 --> 2 HI + S
(b) How many grams of HI are produced from the reaction of 95.4 g of H2S with excess I2?

Stoichiometry: Converting Grams to Grams

If 2.0 mol CH3CH2CH2COOH, 2.0 mol C4H10, and 2.0 mol 
C6H6 are completely combusted in oxygen, which one 
produces the largest number of moles of H2O?

Cytosine, a constituent of deoxyribonucleic acid (DNA), can be represented by the following molecular model. If 0.001 mol of cytosine is submitted to combustion analysis, how many moles of CO2 and how many moles of H2O would be formed? (Gray = C, red = O, blue = N, ivory = H.)

The complete combustion of octane, C8H18, a component of
gasoline, proceeds as follows:
2 C8H181l2 + 25 O21g2¡16 CO21g2 + 18 H2O1g2
(a) How many moles of O2 are needed to burn 1.50 mol of
C8H18?

 Check the balanced equation the mole ratio between these two substances is not 1:1. 

Correct, that mole ratio is 2 AlCl3 to 6 HCl.

Check your mole ratio, this answer implies that three times the number of moles of AlCl3 are produced compared to the number of moles of HCl used.

Check your mole ratio, this answer implies that the ratio of the number of moles of AlCl3 are produced compared to the number of moles of HCl used is 1:2.

 Use the coefficients in the balanced equation to set up the mole to mole conversion factor between aluminum chloride and hydrochloric acid. 

In the following equation how many moles of aluminum chloride are produced from 2.50 mol of hydrochloric acid? 2 Al (s) + 6 HCl(aq) &#8594; 2 AlCl3 (aq) + 3 H2 (g)

Hydrazine, N2H4, once used as a rocket propellant, reacts with oxygen:
N2H4 + O2 --> N2 + 2 H2O
(a) How many grams of O2 are needed to react with 50.0 g of N2H4?

 You have calculated the number of moles of sodium. 

 You have calculated the number of moles of carbon. 

 The molar mass of sodium carbonate is 106.0 g/mol. 

 Correctly done on all conversions involved. 

 You have calculated the mass of carbon rather than sodium carbonate. 

 Avogadro's number converts between atoms and moles, and molar mass between moles and grams. 

How many grams of sodium carbonate, Na2CO3 contain 1.773 &#215; 1017 carbon atoms?

Stoichiometry Made Easy: Stoichiometry Tutorial Part 1

Calculate how many moles of NO2 form when each quantity of
reactant completely reacts.
2 N2O5( g)¡4 NO2( g) + O2( g)
a. 2.5 mol N2O5

An element X forms an iodide 1XI32 and a chloride 1XCl32.
The iodide is quantitatively converted to the chloride when
it is heated in a stream of chlorine:
2 XI3 + 3 Cl2¡2 XCl3 + 3 I2
If 0.5000 g of XI3 is treated with chlorine, 0.2360 g of XCl3 is
obtained. (a) Calculate the atomic weight of the element X.

Aluminum sulfide reacts with water to form aluminum
hydroxide and hydrogen sulfide. (a) Write the balanced
chemical equation for this reaction. (b) How many grams of 
aluminum hydroxide are obtained from 14.2 g of aluminum 
sulfide?

The organic anion <img src="https://lightcat-files.s3.amazonaws.com/problem_images/f44dc784e7b33f89-1665417992737.jpg" alt="" /> is found in most detergents. Assume that the anion under-goes aerobic decomposition in the following manner: C18H29SO3- + 51 O2 → 36 CO2(aq) + 28 H2O (l) + 2 H+(aq) + 2 SO42-(aq) What is the total mass of O2 required to biodegrade 10.0 g of this substance?

 The reaction ratio between phosphorus and tetraphosphorus decoxide is 12 : 3. 

This answer is the number of moles of P4O10.

 Correct on all aspects of the calculation. 

 The equation must be correctly balanced. 

 The coefficients in the balanced equation represent the mole to mole ratios between reactants and products.  Begin by balancing the equation. 

If a match contained 1.00 g of P, how much P4O10 would form if the following equation was obeyed?___ KClO3 + ___ P &#8594; 10 KCl + ___ P4O10

For each of the acid–base reactions, calculate the mass (in grams)
of each acid necessary to completely react with and neutralize
4.85 g of the base.
b. 2 HNO3(aq) + Ca(OH)2(aq)¡2 H2O(l ) + Ca(NO3)2(aq)

Magnesium metal burns in oxygen to form magnesium oxide, MgO. 
(c) How many grams of Mg are needed to react with 25.0 g of O2? How many grams of MgO will result?

An iron ore sample contains Fe2O3 together with other substances.
Reaction of the ore with CO produces iron metal:
Fe2O31s2 + CO1g2¡Fe1s2 + CO21g2
(b) Calculate the number of grams of CO that can react
with 0.350 kg of Fe2O3.

The reaction between potassium superoxide, KO2, and CO2,
4 KO2 + 2 CO2¡2K2CO3 + 3 O2
is used as a source of O2 and absorber of CO2 in selfcontained
breathing equipment used by rescue workers.
(b) How many grams of KO2 are needed to form 7.50 g of O2?

During a certain time period, 4.0 million tons of SO2 were
released into the atmosphere and subsequently oxidized
to SO3. As explained in the Inquiry, the acid rain produced
when the SO3 dissolves in water can damage marble
statues:
CaCO31s2 + H2SO41aq2S CaSO41aq2 + CO21g2 + H2O1l2
(a) How many 500 pound marble statues could be damaged
by the acid rain? (Assume that the statues are pure
CaCO3 and that a statue is damaged when 3.0% of its
mass is dissolved.)

Hydrofluoric acid, HF(aq), cannot be stored in glass bottles 
because compounds called silicates in the glass are attacked 
by the HF(aq). Sodium silicate 1Na2SiO32, for example, reacts 
as follows: 
Na2SiO31s2 + 8 HF1aq2¡ H2SiF61aq2 + 2 NaF1aq2 + 3 H2O1l2 
(b) How many grams of NaF form when 0.500 mol of HF 
reacts with excess Na2SiO3?

An important reaction that takes place in a blast furnace during
the production of iron is the formation of iron metal and CO2
from Fe2O3 and CO. Determine the mass of Fe2O3 required to
form 910 kg of iron. Determine the amount of CO2 that forms
in this process.

The mass in grams is calculated by solving the following proportion for x: 35 g/100 g = 1250 g/ x g

Ammonium nitrate (NH4NO3), a common fertilizer, is 35.0% nitrogen by mass. How much ammonium nitrate contains 1.25 kg of nitrogen?

Automotive air bags inflate when sodium azide, NaN3,
rapidly decomposes to its component elements:
2 NaN31s2¡2 Na1s2 + 3 N21g2
(c) How many grams of NaN3 are required to produce
10.0 ft3 of nitrogen gas, about the size of an automotive
air bag, if the gas has a density of 1.25 g/L?

Utilize the stoichiometric chart to do all your stoichiometric calculations.

Hydrobromic acid dissolves solid iron according to the reaction:
Fe(s) + 2 HBr(aq)¡FeBr2(aq) + H2( g)
What mass of HBr (in g) do you need to dissolve a 3.2-g pure iron
bar on a padlock?

A 3.50 g of an alloy which contains only lead and tin is dissolved
in hot HNO3. Excess sulfuric acid is added to this
solution and 1.57g of PbSO4(s) is obtained. (b) Assuming all
the lead in the alloy reacted to form PbSO4, what was the
amount, in grams, of lead and tin in the alloy respectively?

If the density of ethanol, CH3CH2OH, is 0.789 g/mL, how many milliliters of ethanol are needed to produce 4.8 g of H2O in the following reaction?&nbsp;<img src="https://static.studychannel.pearsonprd.tech/courses/general-chemistry/thumbnails/images/ac9a0a63"class="fr-fic fr-dii">

A certain alcoholic beverage contains only ethanol (C2H6O) and water. When a sample of this beverage undergoes com-bustion, the ethanol burns but the water simply evaporates and is collected along with the water produced by combus-tion. The combustion reaction is 
When a 10.00 g sample of this beverage is burned, 11.27 g of water is collected. What is the mass in grams of ethanol, and what is the mass of water in the original sample?

The combustion of gasoline produces carbon dioxide and water.
Assume gasoline to be pure octane (C8H18) and calculate the
mass (in kg) of carbon dioxide that is added to the atmosphere
per 1.0 kg of octane burned. (Hint: Begin by writing a balanced
equation for the combustion reaction.)

Many home barbeques are fueled with propane gas (C3H8).
What mass of carbon dioxide (in kg) is produced upon the complete
combustion of 18.9 L of propane (approximate contents
of one 5-gallon tank)? Assume that the density of the liquid
propane in the tank is 0.621 g>mL. (Hint: Begin by writing a
balanced equation for the combustion reaction.)

Some progressive hair coloring products marketed to men, such as Grecian Formula 16, contain lead acetate Pb(CH3CO2)2. As the coloring solution is rubbed on the hhair, the Pb2+ ions react with the sulfur atoms in hair proteins to give lead(II) sulfide (PbS), which is black. A typical coloring solution contains 0.3 mass% Pb(CH3CO2)2, and about 2 mL of the solution is used per application. 
(a) Assuming that 30% of the Pb(CH3CO2)2 is converted to PbS, how many milligrams of PbS are formed per application of the coloring solution?

Ethylene gas, C2H4, reacts with water at high temperature to yield ethyl alcohol, C2H6O. 
(a) How many grams of ethylene are needed to react with 0.133 mol of H2O? How many grams of ethyl alcohol will result? 
(b) How many grams of water are needed to react with 0.371 mol of ethylene? How many grams of ethyl alcohol will result?

Assume that gasoline has the formula C8H18 and has a density of 0.703 g/mL. How many pounds of CO2 are produced from the complete combustion of 1.00 gal of gasoline?

Reaction Types and Stoichiometry

Titanium dioxide (TiO2), the substance used as the pigment in white paint, is prepared industrially by reaction of TiCl4 with O2 at high temperature. 
TiCl4 + O2 --> (heat) TiO2 + 2 Cl2 
How many kilograms of TiO2 can be prepared from 5.60 kg of TiCl4?

Stoichiometry Example 1

The answer (x) can be calculated by solving the following proportion: 33.8%/100% = (5 x 14.01 amu)/ x amu

 The mass percent composition of an element is that element&#8217;s percentage of the compound&#8217;s total mass. 

 Zeatin, a plant hormone, is known to have 5 nitrogen atoms in every molecule.  Nitrogen makes up 33.8% of the mass of the molecule.  What is the mass of one molecule in amu? 

When eaten, dietary carbohydrates are digested to yield glu-cose (C6H12O6), which is then metabolized to yield carbon dioxide and water: 
Balance the equation, and calculate both the mass in grams and the volume in liters of the CO2 produced from 66.3 g of glucose, assuming that 1 mol of CO2 has a volume of 25.4 L at normal body temperature.

Automotive air bags inflate when sodium azide, NaN3, 
rapidly decomposes to its component elements: 
2 NaN31s2¡2 Na1s2 + 3 N21g2 
(c) How many grams of NaN3 are required to produce 
10.0 ft3 of nitrogen gas, about the size of an automotive 
air bag, if the gas has a density of 1.25 g/L?

For each of the reactions, calculate the mass (in grams) of the
product that forms when 15.39 g of the underlined reactant
completely reacts. Assume that there is more than enough of
the other reactant.
d. 2 Sr(s) + O2( g)¡2 SrO(s)

One way to make coal burning better for the environment is to remove carbon dioxide from the exhaust gases released from power plants using a compound containing an amine (-NH2) group. The reaction between carbon dioxide and monoethanolamine is: 
CO2(g) + 2 HOCH2CH2NH2(aq) -> HOCH2CH2NH3 +(aq) + HOCH2CH2NHCO2-(aq) 
What mass of monoethanoloamine is required to react with 1.0 kg of carbon dioxide? (LO 3.5) 
(a) 2.8 kg
(b) 1.1 kg
(c) 0.93 kg
(d) 0.53 kg

 There are two nitrate ions in this compound. 

 Correct, this is the formula mass of calcium nitrate. 

 The subscript of two outside the parentheses only refers to the nitrate polyatomic ion and not the calcium. 

 In the two nitrate polyatomic ions there are two atoms of nitrogen total. 

 One of the choices correctly represents the formula mass of calcium nitrate. 

 The formula mass of a compound is the sum of all the atomic masses of the atoms in the compound. 

What is the formula mass of calcium nitrate, Ca(NO3)2?

 The number of moles of potassium chlorate is determined by dividing the mass (5.0 g) by the molar mass of potassium chlorate rather than the molar mass of oxygen.   To convert moles of oxygen to mass, use the molar mass of oxygen rather than potassium chlorate. 

 This is the number of moles of oxygen.   It needs to be converted to grams. 

 Correct on all steps of the calculation. 

 The stoichiometry, from the coefficients in the balanced equation, need to be used to convert from moles of potassium chlorate to moles of oxygen. 

The molar mass of oxygen, O2 is 32.00 g/mol.

 The coefficients in the balanced equation represent the mole to mole ratios between reactants and products.  Begin by converting grams to moles. 

When heated, potassium chlorate decomposes to potassium chloride and molecular oxygen:2 KClO3 &#8594; 2 KCl + 3 O2 How much oxygen could be formed from 5.0 g of potassium chlorate?

The industrial production of hydriodic acid takes place by treatment of iodine with hydrazine (N2H4):
2 I2 + N2H4 --> 4 HI + N2
(a) How many grams of I2 are needed to react with 36.7 g of (N2H4)?

The complete combustion of octane, C8H18, a component of
gasoline, proceeds as follows:
2 C8H181l2 + 25 O21g2¡16 CO21g2 + 18 H2O1g2
(c) Octane has a density of 0.692 g>mL at 20 C. How many
grams of O2 are required to burn 15.0 gal of C8H18 (the
capacity of an average fuel tank)?

Hydrobromic acid dissolves solid iron according to the reaction: 
Fe(s) + 2 HBr(aq)¡FeBr2(aq) + H2( g) 
What mass of HBr (in g) do you need to dissolve a 3.2-g pure iron 
bar on a padlock? What mass of H2 would the complete reaction 
of the iron bar produce?

A mixture containing KClO3, K2CO3, KHCO3, and KCl was
heated, producing CO2, O2, and H2O gases according to the
following equations:
2 KClO31s2¡2 KCl1s2 + 3 O21g2
2 KHCO31s2¡K2O1s2 + H2O1g2 + 2 CO21g2
K2CO31s2¡K2O1s2 + CO21g2
The KCl does not react under the conditions of the reaction. If
100.0 g of the mixture produces 1.80 g of H2O, 13.20 g of CO2,
and 4.00 g of O2, what was the composition of the original
mixture? (Assume complete decomposition of the mixture.)
How many grams of K2CO3 were in the original mixture?

A method used by the U.S. Environmental Protection Agency
(EPA) for determining the concentration of ozone in air is to pass
the air sample through a “bubbler” containing sodium iodide,
which removes the ozone according to the following equation:
O31g2 + 2 NaI1aq2 + H2O1l2¡
O21g2 + I21s2 + 2 NaOH1aq2
(a) How many moles of sodium iodide are needed to remove
5.95 * 10-6 mol of O3?

A railroad tank car derails and spills 36 tons of concen-trated sulfuric acid. The acid is 98.0 mass% H2SO4 and has a density of 1.836 g/mL. 
(b) How many kilograms of sodium carbonate are needed to completely neutralize the acid?

Consider the balanced equation: 
SiO2(s) + 3 C(s)¡SiC(s) + 2 CO(g) 
Complete the table showing the appropriate number of moles of 
reactants and products. If the number of moles of a reactant is 
provided, fill in the required amount of the other reactant, as 
well as the moles of each product that forms. If the number of 
moles of a product is provided, fill in the required amount of each 
reactant to make that amount of product, as well as the amount 
of the other product that forms. 
Mol siO2 Mol C Mol SiC Mol CO 
_____ 1.55 _____ _____

Consider the unbalanced equation for the neutralization of
acetic
acid:
HC2H3O2(aq) + Ba(OH)2(aq)¡H2O(l ) + Ba(C2H3O2)2(aq)
Balance the equation and determine how many moles of
Ba(OH)2 are required to completely neutralize 0.461 mole of
HC2H3O2.

Calculate how many moles of NH3 form when each quantity of 
reactant completely reacts. 
3 N2H4(l )¡4 NH3( g) + N2( g) 
c. 65.3 g N2H4

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1. Intro to General Chemistry

2. Atoms & Elements

4. BONUS: Lab Techniques and Procedures

5. BONUS: Mathematical Operations and Functions

6. Chemical Quantities & Aqueous Reactions

7. Gases

8. Thermochemistry

9. Quantum Mechanics

10. Periodic Properties of the Elements

11. Bonding & Molecular Structure

12. Molecular Shapes & Valence Bond Theory

13. Liquids, Solids & Intermolecular Forces

14. Solutions

15. Chemical Kinetics

16. Chemical Equilibrium

17. Acid and Base Equilibrium

18. Aqueous Equilibrium

19. Chemical Thermodynamics

20. Electrochemistry

21. Nuclear Chemistry

22. Organic Chemistry

23. Chemistry of the Nonmetals

24. Transition Metals and Coordination Compounds

[BOOK CHEM] Clutch Version

Empirical Formula

The empirical formula gives the relative number of atoms.&nbsp;

Percent Yield

The Percent Yield determines how successful the product yield is in a chemical reaction.&nbsp;

Molecular Formula

The&nbsp;molecular formula gives the actual number of atoms.

Naming Ionic Compounds

An ionic compound is composed of a positive ion and a negative ion.&nbsp;

Functional Groups in Chemistry

The Functional Group is the portion of a molecule that is responsible for its chemical reactivity.&nbsp;

Naming Molecular Compounds

Molecular Compounds, also known as covalent compounds, contain only non-metals bonded together.&nbsp;

Naming Ionic Hydrates

An Ionic Hydrate is an ionic compound that is linked to at least one molecule of H2O.&nbsp;

Stoichiometry deals with the numerical relationship between compounds in a balanced chemical equation.

Writing Ionic Compounds

Determining the charges of a cation and anion are fundamental in Writing Ionic Compounds.

Polyatomic Ions

Polyatomic Ions are groups of multiple elements that possess a charge.

Balancing Chemical Equations

Balancing Chemical Equations is the first step in future chemical calculations.

Limiting Reagent

The Limiting Reagent represents the compound that is totally consumed in the reaction.&nbsp;

Combustion Analysis

Under Combustion Analysis, the empirical formula of a compound is determined through a combustion reaction.&nbsp;